Gallium(III)-catalyzed tandem cycloisomerization/Friedel-Crafts alkylation: a facile synthesis of 2,5-disubstituted furans

A tandem cycloisomerization/Friedel-Crafts alkylation of indoles has been achieved in a one-pot process to produce 2,5-disubstituted furans using gallium-catalyzed sequential nucleophilic addition onto metal-activated 1-alkynyl-2,3-epoxy acetates. The reaction proceeds efficiently under mild conditions with complete regioselectivity to afford the substituted furan derivatives in good yields with high diversity.